Few studies have systematically investigated the effects of theory-driven variables that are inherent to the aphasia treatment process, regardless of the specific treatment approach. Furthermore, recent emphasis on the need for intensive aphasia treatment in order to make the long-term neuroplastic changes associated with recovery and rehabilitation following a stroke has led to the notion that more treatment is better. Yet, specific information regarding effective practice distributions and scheduling is limited. The purpose of this proposal is to conduct a series of intervention studies to examine how different treatment variables and practice conditions affect short-term acquisition and long-term maintenance and generalization of a skill in the rehabilitation of chronic aphasia. This is best accomplished by using a single treatment paradigm that has experimental support regarding its efficacy, which accommodates the manipulation of variables such as cueing and feedback, and which has easily observable and measurable outcomes. The selected treatment, Aphasia Scripts, is delivered in a highly controlled computer environment (web, PC, tablet) by an anthropomorphically accurate digital therapist, capable of visually modeling speech and interactively guiding treatment, thereby ensuring treatment independence and fidelity by removing clinician-related variables such as clinician expertise and personality factors that potentially influence treatment outcomes. First, a cross-over study will be conducted to measure the effect of cues on acquisition, maintenance and generalization of script training. Participants will be randomized to an error-reducing condition or an errorful condition. Second, to measure the effect of explicit self-monitoring training and task complexity on acquisition, maintenance and generalization of script training, subjects will be randomly assigned to one of four conditions, that vary by feedback (no feedback versus self-feedback) and script complexity (high versus low complexity). Preliminary findings will be used to modify the existing Aphasia Scripts program. Third, the effect of practice distribution and schedules on acquisition, maintenance and generalization of script training will be assessed using the modified Aphasia Scripts program. Subjects will be randomly assigned to one of four conditions that vary by practice schedule (blocked versus random) and practice distribution (massed versus distributed). The primary outcome measure is the percent of script-related words produced; secondary outcome measures include rate of script related words and measures of grammatical productivity. Results and computational models of acquisition, maintenance and generalization will contribute new evidence to support not just the efficacy and delivery of Aphasia Scripts, but also the application of practice principles to aphasia treatment in general.